How to Get the Query Executed in Laravel 5? DB::getQueryLog() Returning Empty Array

by

By default, the query log is disabled in Laravel 5:
https://github.com/laravel/framework/commit/e0abfe5c49d225567cb4dfd56df9ef05cc297448

You will need to enable the query log by calling:

DB::enableQueryLog();

// and then you can get query log

dd(DB::getQueryLog());

or register an event listener:

DB::listen(
    function ($sql, $bindings, $time) {
        //  $sql - select * from `ncv_users` where `ncv_users`.`id` = ? limit 1
        //  $bindings - [5]
        //  $time(in milliseconds) - 0.38 
    }
);

Some Tips

1. Multiple DB connections

If you have more than one DB connection you must specify which connection to log

To enables query log for my_connection:

DB::connection('my_connection')->enableQueryLog();

To get query log for my_connection:

print_r(
   DB::connection('my_connection')->getQueryLog()
);

2. Where to enable query log ?

For an HTTP request lifecycle, you can enable query log in the `handle` method of some `BeforeAnyDbQueryMiddleware` [middleware][1] and then retrieve the executed queries in the [`terminate`][2] method of the same middleware.

class BeforeAnyDbQueryMiddleware
{
    public function handle($request, Closure $next)
    {
        DB::enableQueryLog();
        return $next($request);
    }

    public function terminate($request, $response)
    {
        // Store or dump the log data...
        dd(
            DB::getQueryLog()
        );
    }
}

A middleware’s chain will not run for artisan commands, so for CLI execution you can enable query log in the artisan.start event listener.

For example you can put it in the bootstrap/app.php file

$app['events']->listen('artisan.start', function(){
    \DB::enableQueryLog();
});

3. Memory

Laravel keeps all queries in memory. So in some cases, such as when inserting a large number of rows, or having a long running job with a lot of queries, this can cause the application to use excess memory.

In most cases you will need the query log only for debugging, and if that is the case I would recommend you enable it only for development.

if (App::environment('local')) {
    // The environment is local
    DB::enableQueryLog();
}

References

More Related Contents:

  1. Laravel 5 – redirect to HTTPS
  2. Laravel : Syntax error or access violation: 1055 Error
  3. How to validate array in Laravel?
  4. Access Controller method from another controller in Laravel 5
  5. How can I convert many statement mysql to laravel eloquent?
  6. What is the difference between find(), findOrFail(), first(), firstOrFail(), get(), list(), toArray()
  7. Can’t install laravel installer via composer
  8. Laravel: validate an integer field that needs to be greater than another
  9. Laravel Request::all() Should Not Be Called Statically
  10. Laravel Checking If a Record Exists
  11. How to execute Stored Procedure from Laravel
  12. Laravel catch TokenMismatchException
  13. Why do I have to run “composer dump-autoload” command to make migrations work in laravel?
  14. How to redirect back to form with input – Laravel 5
  15. How to select all column name from a table in laravel?
  16. Laravel 5 hasMany relationship on two columns
  17. Laravel 5.2 Auth not Working
  18. Call to undefined method Maatwebsite\Excel\Excel::load()
  19. Laravel 5 – Clear Cache in Shared Hosting Server
  20. Laravel 5 change public_path()
  21. ErrorBag is always empty in Laravel 5.2
  22. Laravel 5.2 not reading env file
  23. Fatal error: Class ‘Illuminate\Foundation\Application’ not found
  24. disable csrf in laravel for specific route
  25. SQLSTATE[HY000] [2002] php_network_getaddresses: getaddrinfo failed: nodename nor servname provided, or not known
  26. Custom validator in Laravel 5
  27. laravel 5 : Class ‘input’ not found
  28. Laravel changing timezone not reflecting the correct time
  29. How to remove /public/ from a Laravel URL
  30. Unit Test Laravel’s FormRequest

Leave a Comment